The THERMOLITE® Reactor™ Extreme liner is Sea to Summit’s warmest knitted sleeping bag liner. If your adventures take you to colder climates, the Reactor Extreme will add plenty of warmth to a sleeping bag. In warmer weather, it can be used a ‘stand alone’ sleeping bag. The hollow core fibers of the THERMOLITE® fabric work like hollow polar bear or caribou fur – along with the knitted structure, this traps plenty of insulating air. Super soft and amazingly stretchy, the Reactor Extreme uses a heavier version of THERMOLITE®  to provide extra warmth for an incredibly comfortable night’s sleep. Use one to build your cooler-weather sleep system and to help to keep your sleeping bag clean, too.

• Adds up to 25°F (15°C) of warmth to a sleeping bag
• Stretchy, Thermolite® fabric is incredibly comfortable
  
• 110g/m² fabric is warmer than the 80g/m² Thermolite® used in the standard Reactor
• Works like your favorite cold-weather base layer to trap insulating air and increase warmth
• Easy care – no special soap is needed
• Significantly improves the thermal performance of your sleeping bag
• Comfortable stretchy fabric
• Keeps sleeping bag clean
• Machine wash and air dry - Avoid fabric softeners & dryer sheets to maintain wicking performance
• Packs into its own Ultra-Sil™stuff sack

• Dimensions: 82 in / 208 cm
• Stuff Sack Size: 6.5 x 4.5 in / 17 x 11.5 cm
• Weight: - 14 oz / 399 g

• Thermolite polyester fabric

The origins of Sea to Summit began in 1983 in Perth, Western Australia - a time when lightweight, outdoor products were hard to find in Australia. The original products were developed to outfit an audacious attempt to climb Mt Everest by beginning the ascent at sea level. This gear would need to work at every altitude over several months and be light and durable enough for the 5 month trek. The expedition was a success and so was the gear and the Sea to Summit brand was born.